Simple mouse gestures work, but without visual guide, configuration and without right click + scroll.
Most horrible thing: MDI don't work. Popups opens in new window, like other browsers, instead of new tabs, like old Opera! Alerts currently don't have any chrome, so may be they would develop this later.
Opera Link don't work.
Text selection in links via mouse don't work.
No sidebar.
Verdict: in current state unusable for old Opera users.
1. No tab 'recycle bin' (you can get this with extensions in other browsers, but I always liked that Opera had it out of the box.)
2. The downloader is similar to Chrome's one, and I've always hated Chome's downloader. I want my browser to ask me whether I want to open the file (i.e. save into /tmp and open) or to save. I download a lot of things such as Office documents, tarballs, torrent files (etc) that I don't want to have to manually delete from my downloads folder when I'm done.
I can appreciate that this is a beta version, but right now, it looks a lot like Chrome with a different skin. I just hope it doesn't remain like that for long, as Opera is the one browser that annoys me the least.
Extensions are much slower and annoying to manage. If Opera Next does not include all the features Opera users used to have (the bin is just one of them) then none of them will actually use it. If we wanted Chrome, we would use it.
Having spent 2 mins with it, aside from what has already been mentioned...
No mouse chording (distinct from gestures). Wikipedia even highlights Opera as a key implementation of mouse chording, and now its gone.
http://en.wikipedia.org/wiki/Mouse_chording
No closed tabs drop down. Its not uncommon for me to want to dig out a tab I may have closed 20 tabs ago. Reopening one-by-one is terrible.
No forward slash search (á la Vim, or indeed, Firefox)
If these things aren't tabled for Opera 15's release, then thats it, I'll be back to Firefox after 9 years on Opera. These sort of small features are Opera's bread and butter, things that have become second nature to me, and I suspect many. Certainly for me, its these little things that have kept me on Opera until now.
Where can we go to provide feedback? The OP provides no obvious link.
Trying to be positive, Stash looks like it might be useful.
What makes you think they intend to get all the features we want back in? I hope you're right, but I haven't seen anything to indicate that's the case.
Bookmarks. I can't use the browser without normal bookmarks.
The main reason I use Opera: Editing preferences for every site separately.
Starting from the scratch and reimplementing everything that was slowly improved through many years is impossible. The proper way is replacing/improving piece by piece of the system. The management should have read
I haven't tried Firefox, but I can tell you what I do in Opera: default settings are restrictive, then when I want to enable something on some site, I go to "Edit site preferences". The site name e.g. news.ycombinator.com is already there. And imagine I want to allow everything on the whole ycombinator.com, I just delete "news." then allow what I want (e.g. JavaScript).
That way I enjoy the quietness (by default) of the sites and the higher security of browsing. When I really, really need sites which depend on too much moving parts I start some other browser, but for day-to-day browsing I enjoyed not having to install any extension but still having something like "noscript." If Opera fails, I'll have to discover how to get similar functionality on some other browser.
Simple mouse gestures work, but without visual guide, configuration and without right click + scroll.
Most horrible thing: MDI don't work. Popups opens in new window, like other browsers, instead of new tabs, like old Opera! Alerts currently don't have any chrome, so may be they would develop this later.
Opera Link don't work.
Text selection in links via mouse don't work.
No sidebar.
Verdict: in current state unusable for old Opera users.